Possible Storage Bloating

[timurguvenkaya]

Description

It was observed that ItemStore is unbounded, and add_item does not take any storage deposit. Anyone can bloat the storage, degrade the chain's performance, and make it more costly by adding a massive number of dummy items.

Recommendation

Put a sufficient storage deposit so that it won't be financially viable for a malicious actor to attempt such an attack. Also, add the delete_item function which will delete an item from storage and refund a storage deposit.